1. Field of Invention
The present invention relates to an electromagnetic water treatment apparatus for preventing the occurrence and the attachment of scale or rust along a channel used for the circulation of water, and relates in particular to a water treatment apparatus appropriate for an application that can be used for the treatment of a large volume of water.
2. Related Art
Conventionally, an electromagnetic water treatment apparatus, which applies to water an electric field and a magnetic field to prevent the occurrence and attachment of scale and rust along a channel used for the circulation of water, has been proposed (Japanese Patent No. 2,555,235) and is presently being practically employed.
As is shown in FIG. 5, the presently available electromagnetic water treatment apparatus is so designed that a pair of permanent magnets 31 and 32 and a pair of electrodes 33 and 34, composed of different metals, are attached to a casing 35, and along with the casing 35, collectively define a water passage 30.
According to the principle incorporated into this apparatus, a magnetic field, which is generated by the permanent magnets 31 and 32, and an electric field, which is generated by a weak current that is fed to the electrodes 33 and 34, are applied to water flowing through the water passage 30, which is defined by the casing 35 and the permanent magnets 31 and 32. And as a result, the occurrence and attachment of scale and rust can be effectively prevented.
Originally, the objective of the conventional water treatment apparatus was the treatment of water passing through common cooling towers. However, a need has also been expressed for an electromagnetic water treatment apparatus that can be used to treat water circulating through large factory cooling towers, such as those used for petrochemical or petroleum refineries, and that can effectively prevent the occurrence of scale and rust in such constructs.
Since some of the large cooling towers hold around 1000 tons of water, to obtain the same effects as those provided for smaller conventional installations, an arrangement must be provided that can facilitate the effective application of an electric field and a magnetic field to large volumes of water. However, the sizes of the electrodes that can be employed for the conventional electromagnetic water treatment apparatus are limited due to the size of the apparatus itself, and it would therefore be difficult to use the conventional water treatment apparatus to effectively apply an electric field to a large volume of water. Further, were an arrangement employing large electrodes to be used, a huge electromagnetic water treatment apparatus would be required, and spatially this is not realistic.
To resolve this problem, it is one objective of the present invention to provide an electromagnetic water treatment apparatus that can treat a large volume of water, without the size of the apparatus having to be increased.
To achieve this objective, according to a first aspect of the present invention, an electromagnetic water treatment apparatus comprises:
a pair or pairs of electrodes, which are separated by intervening gaps and are disposed along and individually face water passages, that apply electric fields to water flowing through the water passages; and
magnetic field generation means, so arranged that a magnetic field is applied to the water flowing through the water passages,
wherein the magnetic generation means is located in the vicinity of either a water outlet or an inlet or both in an area or in areas wherein the electrodes are disposed along the water passages.
According to a second aspect of the invention, for the electromagnetic water treatment apparatus of the first aspect, the pair or pairs of electrodes are constructed of materials having different electrochemical potentials.
According to a third aspect of the invention, for the electromagnetic water treatment apparatus of the first or the second aspect, the water passages, along which the electrodes are disposed, are provided in a pipe line in which the water passages are defined by passage walls, positioned at predetermined intervals, that perpendicularly staggered the axial direction of the flow of water through the pipe line and hinder the free movement of water except at openings at the ends of the passage walls. The electrodes are mounted on the facing surfaces of the passage walls and the location of the openings differ for adjacent passage walls.
According to a fourth aspect of the invention, for the electromagnetic water treatment apparatus of the third aspect, the openings are formed at alternate ends of adjacent passage walls between the ends of the passage walls and the inner surface of the pipe line, and are located, for individual adjacent passage walls, at alternate, opposite positions relative to the axis of the pipe line.
According to the electromagnetic water treatment of this invention, the magnetic field generation means that generates a magnetic field is located in the vicinity of the electrodes and is separated by a slight distance from the locations whereat the electrodes are mounted. Therefore, restrictions imposed on the arrangement of the electrodes are reduced, and an electrode arrangement method can be easily adopted that can effectively attain a specific objective, such as an increase in the electrode area, as in the third aspect. Furthermore, since the restrictions placed on the shape of a water treatment apparatus have also been reduced, it is possible to prevent the installation of the electromagnetic water treatment apparatus from becoming difficult due to restrictions that are placed on the shape of the water channel.
It should be noted that, in accordance with the arrangement of the invention, unlike the conventional apparatus, an electric field and a magnetic field are not applied to common space; however, since these fields can be applied to water treated in common over a very short distance, the same effects can be acquired as are obtained by applying the electric field and the magnetic field to common space.
According to the invention, preferably, the electrodes are composed of different types of conductive materials that, because of their differing electrochemical potentials, are relatively negative and positive. At this time, no limitations are placed on the materials and the material combinations that can be used. For example, Al, Zn, Pb or Mg can be used for negative electrodes, and carbon, Pt, stainless steel or Ti can be used for positive electrodes. When a pair of electrodes such as these is disposed along a water passage, and the electrodes are connected electrically, a current will flow across the gap between the electrodes, and an electric field will be applied to the water flowing through the water passage. It should be noted that the electrodes may be connected directly or via a resistor, and that when a resistor is employed, the strength of the electric field applied to the water can be adjusted by changing the resistance of the resistor.
An electric field may also be generated by using a battery to apply a potential to the electrodes, and in this case, the electrodes need not always be formed of different types of materials having different electrochemical potentials.
In actuality, any type of electrodes can be employed, just so long as they are arranged facing a water passage and can apply an electric field to water flowing through the passage. Further, the shapes of the electrodes and the sizes of the gaps between them, and the number of electrodes that can be used and their locations are not specifically controlled. It must be understood, however, that to obtain the large electrode area that is required when a large volume of water is to be treated, it is preferable, as in the third aspect, that a plurality of passage walls be employed that are arranged so that they stagger and are perpendicular to the axial direction of the pipe line and the direction of movement of the water, and that the electrodes be arranged along these passage walls. The movement of water through the pipe line, which is hindered by the passage walls, is facilitated by partial openings that are formed to permit the water to flow through the pipe line.
With this arrangement, the water passages along which the electrodes can be disposed are considerably extended, without increasing the size of the apparatus, and accordingly, there is a corresponding increase in the area occupied by the electrodes arranged along the water passages. At this time, since the water winds between the passage walls and through the alternately positioned openings between the passage walls and the interior wall of the pipe line (relative to the axial direction of the water flow through the pipe line), the electric fields that are generated by the electrodes mounted on the passage walls can be effectively applied to the water. And when, for individual adjacent passage walls, the openings are alternately located at opposite positions relative to the axis of the pipe line, substantially, the water will flow along all the electrodes. Thus, it is even more ensured that an electric field will be effectively applied to the water.
The water passages are normally provided in the pipe line. And in order to apply the magnetic field to the water, the magnetic field generation means is located in the vicinity of at least either the outlet or the inlet for the water passages along which the electrodes are arranged. When the magnetic field generation means is located at least one place regardless of the outlet or the inlet, the effects, including a synergistic effect, of the magnetic field and the electric fields generated by the electrodes can be provided for the water. In order to more precisely provide a synergistic effect for the magnetic field and the electric field, it is preferable that magnetic field generation means be positioned at both the water outlet and inlet. In this case, the vicinity of the outlet or the inlet generally means the external area adjacent to the outlet or the inlet, because the external portion is less affected by the arrangement of the electrodes.
The magnetic field generation means can be provided by arranging magnets so the a magnetic field is applied to the water passages. The magnets that are used may be either permanent magnets or solenoids, but generally, permanent magnets are employed for which the application of electricity is not required.
The magnets, in this case, are so arranged the faces of opposed magnets that generate a magnetic field have different polarities. However, the same polarity may be used for opposing faces, and depending on the arrangement that is employed, the magnetic faces may not be even be located opposite each other.